BRATTLEBORO — More than 1,200 anti-nuclear protesters flocked to the Brattleboro Common on Saturday and listened to three of the state’s top politicians — Gov. Peter Shumlin, U.S. Sen. Bernard Sanders and Attorney General William Sorrell — take turns criticizing Entergy Nuclear and its Vermont Yankee nuclear power plant.

On a picture-perfect Saturday afternoon, people brought “Defend Democracy” T-shirts and anti-nuclear buttons, listened to Afro-beat music and watched street performer “Will Nukem” before the state’s political top guns took over.

All three said Vermont was in a battle for state’s rights, and that Vermont should be able to determine that it didn’t want a nuclear power plant within its borders, safety issues aside.

And they said it was clear that the “power of corporations and their money” was prevailing over what they said was grassroots democracy that wanted the 40-year-old plant shut down and dismantled.

Shumlin, a lifelong Putney resident who represented Windham County before being elected governor two years ago, said Entergy Nuclear had broken promise after promise to the citizens of the state, state government and the Vermont Legislature since it bought Vermont Yankee 10 years ago.

“Thank you for standing up to Entergy Lousiana,” Shumlin said. “We will retire Vermont Yankee on schedule with your help.

‘‘Entergy has gone back on its word time and time again, and its history in Vermont is littered with broken promises,’’ said Shumlin to loud applause. He said the state would continue to push to shut down Vermont Yankee.

“If you do business in Vermont, you keep your word,” he said.

Afterward, Shumlin said the state didn’t take Entergy Nuclear to court last month to force the reactor to shut down, even though its state permit expired March 21, because it was clear from a federal court decision that Entergy could continue operating while the state permit request was pending.

Entergy applied for an extension of its original state certificate of public good in 2008 from the Public Service Board, but that proceeding has been on hold for more than two years since the Vermont Senate voted 26-4 to deny Entergy a permit extension.

The Public Service Board has recently reopened the case, and said it will start from scratch since much of the testimony is stale, and some state law has been ruled inadmissible.

But that didn’t stop Shumlin from rallying the crowd in favor of an immediate shutdown.

How many in the crowd had Vermont driver’s licenses, the governor wanted to know.

A vast majority held up their hands.

“How many would drive without their license?” Shumlin asked. Only a few held up their hands.

“That’s the situation with Entergy Louisiana,” Shumlin said.

Shumlin said later that he had met personally with New York Gov. Andrew Cuomo about New York joining the Vermont suit against Entergy in some way.

Cuomo has said publicly that he wants the Entergy-owned Indian Point reactors shut down when their licenses expire.

Shumlin, who made national news on Friday for his bare tale of eluding four bears raiding his backyard birdfeeders, made light of the story, joking that the bears “came from Entergy.”

One protester held a “Bear Up Guv” sign in the crowd, while most of the signs called for Yankee’s immediate shutdown. Dozens of “Vermont Yankee evacuation zone” signs were on the Common, a reference that the rally was being held within the 10-mile evacuation zone that surrounds the Vernon nuclear reactor.

“We are demanding justice for an agreement made 40 years ago,” said Sanders, who drew the loudest cheers. He said the state had the right to determine a “safe energy future for our kids and grandkids.”

Regulators from the Nuclear Regulatory Commission have never said no to the nuclear plants wanting to keep operating, Sanders said. “Something is wrong,” he said.

Sanders said that nuclear power was a dead-end source of power, and that the state should be commended for taking on a big state’s rights legal fight.

Sorrell, who is heading up the state’s fight against Entergy Nuclear in the federal court system, asked the crowd, “Does democracy need defending?”

“You bet it does,” he said.

Sorrell said he was actively working to solicit support for the federal case, which is now in the 2nd Circuit Court of Appeals in New York.

Sorrell said it would likely be this fall before oral arguments are heard in the case. The state must file its appeal brief later this spring.

The attorney general, who is running for reelection and faces a primary challenge in August, said U.S. District Judge J. Garvan Murtha has set some very dangerous legal precedents that went far beyond nuclear power issues.

Saturday’s rally was the second anti-nuclear demonstration in Brattleboro in three weeks, but unlike a rally and march on Entergy’s corporate offices, no one was arrested.

Organizers from the Safe and Green Energy Alliance, a new coalition of about a dozen anti-nuclear groups in the region, said it was important to show that people are unhappy with Entergy’s operation of Yankee and its continued operation of the plant. Organizers estimated the crowd at between 1,500 and 2,000 people.